Swedish Patent no. 452,951 describes a lowering apparatus that is to be used from buildings. This apparatus is not suited for universal applications. It is poorly suited for suspending people from their body which is required for mast assembly workers on oil platforms and the like.
U.S. Pat. No. 659,093 describes a lowering apparatus with a rope block where a grooved brake lever acts as the brake unit. However, the braking effect is difficult to control and so this device may not be too easy to use. The breaking effect is also difficult to adjust due to people having differing weights. This means that either children are lowered too slowly, or heavier adults will be lowered too quickly. Neither of these lowering devices are suited for releasing a person who is hanging unconscious, for example on a power line pole.